[PATCH v14 10/18] vmscan: remove shrink_control arg from do_try_to_free_pages()

Vladimir Davydov
2013-12-16T12:23:21Z

There is no need passing on a shrink_control struct from
try_to_free_pages() and friends to do_try_to_free_pages() and then to
shrink_zones(), because it is only used in shrink_zones() and the only
field initialized on the top level is gfp_mask, which is always equal to
scan_control.gfp_mask. So let's move shrink_control initialization to
shrink_zones().

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Glauber Costa <glommer@openvz.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
---
mm/vmscan.c | 32 ++++++++++++--------------------
1 file changed, 12 insertions(+), 20 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 035ab3a..33b356e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2274,8 +2274,7 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc)
* further reclaim.
*/
static bool shrink_zones(struct zonelist *zonelist,
- struct scan_control *sc,
- struct shrink_control *shrink)
+ struct scan_control *sc)
{
struct zoneref *z;
struct zone *zone;
@@ -2284,6 +2283,9 @@ static bool shrink_zones(struct zonelist *zonelist,
unsigned long lru_pages = 0;
bool aborted_reclaim = false;
struct reclaim_state *reclaim_state = current->reclaim_state;
+ struct shrink_control shrink = {
+ .gfp_mask = sc->gfp_mask,
+ };

/*
* If the number of buffer_heads in the machine exceeds the maximum
@@ -2293,7 +2295,7 @@ static bool shrink_zones(struct zonelist *zonelist,
if (buffer_heads_over_limit)
sc->gfp_mask |= __GFP_HIGHMEM;

- nodes_clear(shrink->nodes_to_scan);
+ nodes_clear(shrink.nodes_to_scan);

for_each_zone_zonelist_nodemask(zone, z, zonelist,
gfp_zone(sc->gfp_mask), sc->nodemask) {
@@ -2308,7 +2310,7 @@ static bool shrink_zones(struct zonelist *zonelist,
continue;

lru_pages += zone_reclaimable_pages(zone);
- node_set(zone_to_nid(zone), shrink->nodes_to_scan);
+ node_set(zone_to_nid(zone), shrink.nodes_to_scan);

if (sc->priority != DEF_PRIORITY &&
!zone_reclaimable(zone))
@@ -2353,7 +2355,7 @@ static bool shrink_zones(struct zonelist *zonelist,
* LRU pages over slab pages.
*/
if (global_reclaim(sc)) {
- shrink_slab(shrink, sc->nr_scanned, lru_pages);
+ shrink_slab(&shrink, sc->nr_scanned, lru_pages);
if (reclaim_state) {
sc->nr_reclaimed += reclaim_state->reclaimed_slab;
reclaim_state->reclaimed_slab = 0;
@@ -2400,8 +2402,7 @@ static bool all_unreclaimable(struct zonelist *zonelist,
* else, the number of pages reclaimed
*/
static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
- struct scan_control *sc,
- struct shrink_control *shrink)
+ struct scan_control *sc)
{
unsigned long total_scanned = 0;
unsigned long writeback_threshold;
@@ -2416,7 +2417,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
vmpressure_prio(sc->gfp_mask, sc->target_mem_cgroup,
sc->priority);
sc->nr_scanned = 0;
- aborted_reclaim = shrink_zones(zonelist, sc, shrink);
+ aborted_reclaim = shrink_zones(zonelist, sc);

total_scanned += sc->nr_scanned;
if (sc->nr_reclaimed >= sc->nr_to_reclaim)
@@ -2579,9 +2580,6 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
.target_mem_cgroup = NULL,
.nodemask = nodemask,
};
- struct shrink_control shrink = {
- .gfp_mask = sc.gfp_mask,
- };

/*
* Do not enter reclaim if fatal signal was delivered while throttled.
@@ -2595,7 +2593,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
sc.may_writepage,
gfp_mask);

- nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
+ nr_reclaimed = do_try_to_free_pages(zonelist, &sc);

trace_mm_vmscan_direct_reclaim_end(nr_reclaimed);

@@ -2662,9 +2660,6 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK),
};
- struct shrink_control shrink = {
- .gfp_mask = sc.gfp_mask,
- };

/*
* Unlike direct reclaim via alloc_pages(), memcg's reclaim doesn't
@@ -2679,7 +2674,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
sc.may_writepage,
sc.gfp_mask);

- nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
+ nr_reclaimed = do_try_to_free_pages(zonelist, &sc);

trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);

@@ -3335,9 +3330,6 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
.order = 0,
.priority = DEF_PRIORITY,
};
- struct shrink_control shrink = {
- .gfp_mask = sc.gfp_mask,
- };
struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
struct task_struct *p = current;
unsigned long nr_reclaimed;
@@ -3347,7 +3339,7 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
reclaim_state.reclaimed_slab = 0;
p->reclaim_state = &reclaim_state;

- nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
+ nr_reclaimed = do_try_to_free_pages(zonelist, &sc);

p->reclaim_state = NULL;
lockdep_clear_current_reclaim_state();
--
1.7.10.4